// ****************************************************************************
// * This file is part of the HqMAME project. It is distributed under         *
// * GNU General Public License: http://www.gnu.org/licenses/gpl-3.0          *
// * Copyright (C) Zenju (zenju AT gmx DOT de) - All Rights Reserved          *
// *                                                                          *
// * Additionally and as a special exception, the author gives permission     *
// * to link the code of this program with the MAME library (or with modified *
// * versions of MAME that use the same license as MAME), and distribute      *
// * linked combinations including the two. You must obey the GNU General     *
// * Public License in all respects for all of the code used other than MAME. *
// * If you modify this file, you may extend this exception to your version   *
// * of the file, but you are not obligated to do so. If you do not wish to   *
// * do so, delete this exception statement from your version.                *
// ****************************************************************************

#ifndef XBRZ_HEADER_3847894708239054
#define XBRZ_HEADER_3847894708239054

#include "config.h"
#include <cstddef> //size_t
#include <limits>
#include <stdint.h> //uint32_t

namespace xbrz
{
/*
-------------------------------------------------------------------------
| xBRZ: "Scale by rules" - high quality image upscaling filter by Zenju |
-------------------------------------------------------------------------
using a modified approach of xBR:
http://board.byuu.org/viewtopic.php?f=10&t=2248
- new rule set preserving small image features
- highly optimized for performance
- support alpha channel
- support multithreading
- support 64-bit architectures
- support processing image slices
- support scaling up to 6xBRZ
*/

enum ColorFormat // from high bits -> low bits, 8 bit per channel
{ RGB,           // 8 bit for each red, green, blue, upper 8 bits unused
  ARGB,          // including alpha channel, BGRA byte order on little-endian machines
};

/*
-> map source (srcWidth * srcHeight) to target (scale * width x scale * height) image, optionally
processing a half-open slice of rows [yFirst, yLast) only
-> support for source/target pitch in bytes!
-> if your emulator changes only a few image slices during each cycle (e.g. DOSBox) then there's no
need to run xBRZ on the complete image:
   Just make sure you enlarge the source image slice by 2 rows on top and 2 on bottom (this is the
additional range the xBRZ algorithm is using during analysis)
   Caveat: If there are multiple changed slices, make sure they do not overlap after adding these
additional rows in order to avoid a memory race condition
   in the target image data if you are using multiple threads for processing each enlarged slice!

THREAD-SAFETY: - parts of the same image may be scaled by multiple threads as long as the [yFirst,
yLast) ranges do not overlap!
               - there is a minor inefficiency for the first row of a slice, so avoid processing
single rows only; suggestion: process 8-16 rows at least
*/
void scale(size_t factor, // valid range: 2 - 6
           const uint32_t *src, int srcWidth, int srcHeight, int srcPitch, uint32_t *trg,
           int trgPitch, ColorFormat colFmt, const ScalerCfg &cfg = ScalerCfg(), int yFirst = 0,
           int yLast = std::numeric_limits<int>::max()); // slice of source image

void nearestNeighborScale(const uint32_t *src, int srcWidth, int srcHeight, uint32_t *trg,
                          int trgWidth, int trgHeight);

enum SliceType {
        NN_SCALE_SLICE_SOURCE,
        NN_SCALE_SLICE_TARGET,
};
void nearestNeighborScale(const uint32_t *src, int srcWidth, int srcHeight,
                          int srcPitch, // pitch in bytes!
                          uint32_t *trg, int trgWidth, int trgHeight, int trgPitch, SliceType st,
                          int yFirst, int yLast);

// parameter tuning
bool equalColorTest(uint32_t col1, uint32_t col2, ColorFormat colFmt, double luminanceWeight,
                    double equalColorTolerance);

//########################### implementation ###########################
inline void nearestNeighborScale(const uint32_t *src, int srcWidth, int srcHeight, uint32_t *trg,
                                 int trgWidth, int trgHeight)
{
        nearestNeighborScale(src,
                             srcWidth,
                             srcHeight,
                             srcWidth * sizeof(uint32_t),
                             trg,
                             trgWidth,
                             trgHeight,
                             trgWidth * sizeof(uint32_t),
                             NN_SCALE_SLICE_TARGET,
                             0,
                             trgHeight);
}
}

#endif
